1. Field of the Invention
The subject invention relates to disposable transducer and other systems employing a disposable component having electrically adjustable or compensable parameters, and relates also to disposable transducer or other systems employing a component that may be exposed to sterilization inimical to such disposable component.
2. Information Disclosure Statement
The following disclosure statement is made pursuant to the duty of disclosure imposed by law and formulated in 37 CFR 1.56(a). No representation is hereby made that information thus disclosed in fact constitutes prior art, inasmuch as 37 CFR 1.56(a) relies on a materiality concept which depends on uncertain and inevitably subjective elements of substantial likelihood and reasonableness and inasmuch as a growing attitude appears to require citation of material which might lead to a discovery of pertinent material though not necessarily being of itself pertinent. Also, the following comments contain conclusions and observations which have only been drawn or become apparent after conception of the subject invention or which contrast the subject invention or its merits against the background of developments which may be subsequent in time or priority.
U.S. Pat. No. 3,831,588, by W. Rindner, issued Aug. 27, 1974, discloses a calibration system for a pressure sensing device wherein the pressure in the diaphragm chamber is varied by known amounts, thereby enabling calibration of the device in situ.
U.S. Pat. No. 3,894,535, by R. L. Cannon et al, issued July 15, 1975, discloses a blood pressure monitoring system with a manual control to compensate for the zero-offset of a pressure transducer when zero pressure is applied thereto.
U.S. Pat. No. 4,112,272, by S. E. Jonsson et al, issued Sept. 5, 1978, discloses an automatic zero balance and calibration mechanism controlled by a switch for a pressure converter device.
U.S. Pat. No. 4,232,373, by L. B. Jackson et al, issued Nov. 4, 1980, discloses a compensator system monitoring the response of a fluidic transducer and using that response to generate an error signal which controls the further filtering of the response in order to compensate for the portion of the response which is due to the transducer and not to the phenomena being measured, and also discloses various precalibration techniques from a variety of sources.
U.S. Pat. No. 4,325,382, by S. Miodownik, issued Apr. 20, 1982, proposes the use of a tunable active filter in the signal path between a transducer and a pressure indicator and adapts the frequency parameters of such filter to that of the catheter in real time, for various compensation purposes.
U.S. Pat. No. 4,201,222, by T. Haase, issued May 6, 1980, discloses an optical catheter using optical fibers for conducting light to and from an optical sensor, and employing a light modulator and optical multiplexer system for reading different parameters.
In a somewhat different vein, systems are known which indicate to an observer when a disposable apparatus or component has been sterilized for reuse. In this respect, there are stickers, labeled AMSCO, which have a blue stripe that turns black when exposed to sterilizing steam, and another stripe that assumes a rusty color when exposed to sterilizing ethylene oxide gas.
Despite a variety of proposals of this type, there persisted a need for technologically and economically disposable transducer and similar systems, as well as for safeguards against inimical effects of sterilization of components, and for improved calibration techniques and systems.